| 摘要 |
PURPOSE:To perform the rapid removal of sludge in the flocculation of a intensely-colored organic liquid, by adding lime to make the waste water strong alkaline, and neutralizing the waste between precipitation and biological treatment. CONSTITUTION:A deeply-colored organic waste liquid such as a pulp mill waste liquor is supplied to a flocculating tank 1 where proper amounts of an aluminum salt, e.g. aluminum sulfate, and lime, e.g. slaked lime, are added to adjust pH of the waste water to 11.5-12.5. On this occassion, the aluminum salt is added to the flocculating tank 1 at first, the waste water is mixed for 1-5min, and then powdery or slurry lime is supplied from a position of 0-10cm above the water surface in the flocculating tank 1 by a quantitative feeder. The neutralized waste water is supplied to a biological treating tank 4 to remove BOD by the action of activated sludge. Sludge recovered from a precipitating cell 2 is supplied to a mixing tank 5 where a proper amount of lime is added to adjust the pH of the sludge to 12-12.5 and to fix coloring substance. |
